Depending on the processed material from each drill must be properly sharpened. To verify the correct angle will help a specially prepared square plate of copper or aluminium with a thickness of 1 mm.
To become operational protractor enough to cut it cut, as shown in the picture: a large cutout at an angle of 120 degrees, the other half is 60 degrees and the surviving corner of a square is 90.
Recommend to read
AND CART, AND A CHAIR
From spring to autumn, you can see a common picture, old young goes to the cottage, carrying a truck with a heavy load In these hours and the city is crowded, and trains, people are...
FUN FOR ADULTS
Shown in the figure and pattern of a simple toy has survived from the ancient Celts. Most interesting is that it was a pleasure to play not only children but adults as unusual properties...
